Change log for definition version 1.251.917.0 RSS feed icon

This page lists what has changed in the most recent definitions update for Windows Defender Antivirus and Microsoft Security Essentials.

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The following tables list the new and updated definitions for the version you select here. You can choose from the 20 latest updates, and the most recent update is shown by default:

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Definition available date: Sep 14,2017 01:41 AM UTC

New definitions

HackTool:Win32/AutoKMSmoderate
HackTool:Win32/PasswordFoxmoderate
Backdoor:MSIL/Hamaetot.Asevere
Backdoor:MSIL/Orcusrot.Asevere
Backdoor:Win32/Bezigate.Bsevere
Backdoor:Win32/Hostilsevere
Backdoor:Win32/Protos.Asevere
Backdoor:Win32/Rescoms.Asevere
Backdoor:Win32/Rescoms.Bsevere
Backdoor:Win32/Xiclog.Asevere
DDoS:Linux/Lightaidra!rfnsevere
PWS:Win32/Primarypass.Asevere
Ransom:Win32/Genasomsevere
Ransom:Win32/Loktrom.Bsevere
Ransom:Win32/Troldesh.Asevere
Ransom:Win32/WannaCrypt!bitsevere
Trojan:JS/HideLink!rfnsevere
Trojan:MSIL/Chippedout.A!dhasevere
Trojan:O97M/Madeba.A!detsevere
Trojan:PDF/Fraud!dtasevere
Trojan:PDF/Phishsevere
Trojan:PDF/Phish!dtasevere
Trojan:PowerShell/Chippedout.A!dhasevere
Trojan:Win32/Avatpow.C!bitsevere
Trojan:Win32/Bancteian.Bsevere
Trojan:Win32/Claretore.Lsevere
Trojan:Win32/CoinMiner.AC!bitsevere
Trojan:Win32/Dynamer!rfnsevere
Trojan:Win32/Hioles.Dsevere
Trojan:Win32/Malexsevere
Trojan:Win32/Skeeyah.A!rfnsevere
Trojan:Win32/Swrort.Asevere
TrojanClicker:JS/Faceliker!rfnsevere
TrojanDownloader:Win32/Eldycowsevere
TrojanDownloader:Win32/Pogolcil.Asevere
TrojanDownloader:Win32/Unruy.Hsevere
TrojanDropper:Win32/Gepyssevere
TrojanDropper:Win32/Lamechisevere
TrojanProxy:Win32/Bunitu.Q!bitsevere
TrojanSpy:MSIL/Yakbeex.Bsevere
TrojanSpy:Win32/Loyeetro.Asevere
TrojanSpy:Win32/Plimrost.Bsevere
TrojanSpy:Win32/Ranbyussevere
Worm:Win32/Dorkbotsevere
Worm:Win32/Dorkbot.Isevere
Worm:Win32/Hamweqsevere
Worm:Win32/Mamianunesevere
Worm:Win32/Rebhip.Vsevere

Updated definitions

HackTool:MSIL/Boilod.Ahigh
SoftwareBundler:MSIL/Wizremhigh
SoftwareBundler:Win32/ICLoaderhigh
SoftwareBundler:Win32/Mizenotahigh
Trojan:Win32/Startpagehigh
HackTool:Win32/Broduplomoderate
HackTool:Win32/Mailpassviewmoderate
Backdoor:MSIL/Bladabindi!rfnsevere
Backdoor:MSIL/Lizarbot.Asevere
Backdoor:MSIL/Noancooe.Asevere
Backdoor:MSIL/Noancooe.Csevere
Backdoor:MSIL/Sisbot.Asevere
Backdoor:Win32/Beksnoc.Asevere
Backdoor:Win32/Bifrosesevere
Backdoor:Win32/Blohi.Bsevere
Backdoor:Win32/Caklsevere
Backdoor:Win32/Cycbot.Bsevere
Backdoor:Win32/Delfsevere
Backdoor:Win32/Farfli.BWsevere
Backdoor:Win32/Farfli.Zsevere
Backdoor:Win32/Gaertob.Asevere
Backdoor:Win32/IRCbotsevere
Backdoor:Win32/Kelihossevere
Backdoor:Win32/Lybsus.Asevere
Backdoor:Win32/NetWiredRC.Dsevere
Backdoor:Win32/PcClientsevere
Backdoor:Win32/Qakbot!rfnsevere
Backdoor:Win32/Qakbot.Tsevere
Backdoor:Win32/Rbotsevere
Backdoor:Win32/Simbotsevere
Backdoor:Win32/Tenpeqsevere
Backdoor:Win32/Turkojansevere
Backdoor:Win32/Votwup.Dsevere
Backdoor:Win32/Xtrat.ACsevere
Backdoor:Win32/Zegostsevere
DDoS:Win32/Nitol.Asevere
DDoS:Win32/Nitol.Bsevere
Exploit:Win32/MS06040severe
Exploit:Win32/Shellcodesevere
PWS:MSIL/Mintluks.Asevere
PWS:Win32/Fareitsevere
PWS:Win32/Ldpinchsevere
PWS:Win32/Lineagesevere
PWS:Win32/Lmirsevere
PWS:Win32/Stealer.Msevere
PWS:Win32/Tibia.ARsevere
PWS:Win32/Zbot!rfnsevere
PWS:Win32/Zbot!VMsevere
Ransom:MSIL/JigsawLocker.Asevere
Ransom:Win32/LockScreensevere
Rogue:Win32/FakePAVsevere
Rogue:Win32/Winwebsecsevere
Spammer:Win32/Tedroo.Asevere
Trojan:BAT/Olsa!infsevere
Trojan:JS/Redirector!rfnsevere
Trojan:MSIL/Blinerarch.AYsevere
Trojan:MSIL/Eskimo.Asevere
Trojan:MSIL/Vbato.Asevere
Trojan:Win32/Adclicker.AQsevere
Trojan:Win32/Alureonsevere
Trojan:Win32/Alureon!infsevere
Trojan:Win32/Beaugritsevere
Trojan:Win32/BHOsevere
Trojan:Win32/Bicone.Bsevere
Trojan:Win32/Blocix.Asevere
Trojan:Win32/Conhook.Dsevere
Trojan:Win32/Delfsevere
Trojan:Win32/Desurou.Asevere
Trojan:Win32/Dynamer!acsevere
Trojan:Win32/Estiwir.Csevere
Trojan:Win32/Goabeny!rfnsevere
Trojan:Win32/Helpud.Asevere
Trojan:Win32/Iflarsevere
Trojan:Win32/Injeber.A!bitsevere
Trojan:Win32/Jhee.Vsevere
Trojan:Win32/Killavsevere
Trojan:Win32/Neurevt.ABsevere
Trojan:Win32/Rebhip.AA!bitsevere
Trojan:Win32/Salgorea.C!dhasevere
Trojan:Win32/Sirefef.BCsevere
Trojan:Win32/Sirefef.Vsevere
Trojan:Win32/Skeeyahsevere
Trojan:Win32/Suloc.Asevere
Trojan:Win32/Taloc.Dsevere
Trojan:Win32/Veslornsevere
Trojan:Win32/Woripecssevere
Trojan:Win32/Zonsterarch.ABsevere
Trojan:Win32/Zonsterarch.ACsevere
Trojan:Win32/Zonsterarch.BWsevere
Trojan:WinNT/Alureon.Hsevere
Trojan:WinNT/Alureon.Lsevere
Trojan:WinREG/Startpage.Esevere
TrojanDownloader:JS/Nemucodsevere
TrojanDownloader:MSIL/Pstinb.Asevere
TrojanDownloader:O97M/Donoffsevere
TrojanDownloader:VBS/Adodb.Dsevere
TrojanDownloader:Win32/Agentsevere
TrojanDownloader:Win32/Cekarsevere
TrojanDownloader:Win32/Dofoil!rfnsevere
TrojanDownloader:Win32/Dofoil.ACsevere
TrojanDownloader:Win32/Filachaem.Asevere
TrojanDownloader:Win32/Perkeshsevere
TrojanDownloader:Win32/Renossevere
TrojanDownloader:Win32/Tugspay.Asevere
TrojanDownloader:Win32/Waledac.ALsevere
TrojanDropper:MSIL/Hostwack.Asevere
TrojanDropper:Win32/Agentsevere
TrojanDropper:Win32/Dinome.Asevere
TrojanDropper:Win32/Dowque.Asevere
TrojanDropper:Win32/Minmal.Asevere
TrojanDropper:Win32/Randrew.A!bitsevere
TrojanDropper:Win32/Sirefef.Bsevere
TrojanDropper:Win32/VBsevere
TrojanProxy:Win32/Horstsevere
TrojanSpy:MSIL/Golroted.Asevere
TrojanSpy:MSIL/Golroted.Bsevere
TrojanSpy:MSIL/Golroted.Esevere
TrojanSpy:MSIL/Golroted.Fsevere
TrojanSpy:MSIL/Hoetou.ACsevere
TrojanSpy:MSIL/Neos.Asevere
TrojanSpy:MSIL/Omaneat.Asevere
TrojanSpy:MSIL/Omaneat.Bsevere
TrojanSpy:MSIL/Omaneat.Csevere
TrojanSpy:MSIL/Plimrost.Bsevere
TrojanSpy:Win32/Bancossevere
TrojanSpy:Win32/Pophot.K!dllsevere
TrojanSpy:Win32/Tiop.Asevere
VirTool:MSIL/Injectorsevere
VirTool:MSIL/Subti.Nsevere
VirTool:Win32/CeeInjectsevere
VirTool:Win32/DelfInjectsevere
VirTool:Win32/FireJoiner.A!drsevere
VirTool:Win32/Injectorsevere
VirTool:Win32/Vbindersevere
VirTool:Win32/VBInjectsevere
Worm:AutoIt/Nuqelsevere
Worm:MSIL/Ainslot.Asevere
Worm:Win32/Ainslot.Asevere
Worm:Win32/Arhost.Asevere
Worm:Win32/Autorunsevere
Worm:Win32/Gamarue!rfnsevere
Worm:Win32/Gamarue.Isevere
Worm:Win32/NewWormsevere
Worm:Win32/Nuj.Asevere
Worm:Win32/Rebhipsevere
Worm:Win32/Rebhip.Asevere
Worm:Win32/Soglueda.Asevere
Worm:Win32/VBsevere
Worm:Win32/Wergimog.Asevere